Long error message when try to extrude and input box is empty? (I can now no longer use blender)
I expect that the copy of flip fluids wasn't installed right and is causing this issue. The flip fluids addon found on github is not a simple python addon that can be copied into place, it needs to be compiled for the target system before installing.

As you have reinstalled blender, the issue would likely be in your user settings. Find the USER path for your system and move or rename the folder with the version number (2.79) to say 2.79-bad. This will prevent blender from loading anything in there.

Once blender starts without any user config files, you can try replacing some files to try and restore to where you were before the issue. In the config folder, try replacing the startup.blend, userpref.blend and bookmarks.txt. Inside the scripts, you could try replacing some other addons you may have installed if you know they belong to an addon that you can't find the original files for. If you do this a couple of files at a time you can identify any that cause the issue.